Fix re-create checkbox (#1857)

* toggle_style_button : calls to options.afterButtonPressed replaced by call to class function afterButtonPressed to allow default call to base button settings
quill_icon_button: L26 build for isSelected updated to call afterButtonPressed = same as if not selected
QuillController _updateSelection removed param=source because not used; added new param insertNewline when true set tog to style of preceding char (last entered); updated replaceText to call _updateSelection for NL
document collectStyle:  Selecting the start of a line, user expects the style to be the visible style of the line including inline styles

* color_button calls afterButtonPressed
insert at start of line uses style for line

* Remove comments

* Fix formatting issue

* Fix FontFamily and Size button actions

* Fix FontFamily and Size button actions

* Value setting Stateful toolbar buttons derive from base class

* Rename base class as QuillToolbarBaseValueButton

* Fixes for before_push script

* Removed deprecated functions

* Move clipboard actions to QuillController

* Fix: collectAllIndividualStylesAndEmbed for result span

* Add: Clipboard toolbar buttons

* export: Clipboard toolbar buttons

* Fix: Dividers not shown in toolbar when multiRowsDisplay.
Fix: Toolbar drop buttons clipped when !multiRowsDisplay

* Add: test for QuillController clipboard
Dart Formatted

* Localizations updated

* QuillControllerConfigurations and clipboard paste

* Fix: CheckList action

---------

Co-authored-by: Douglas Ward <dward@scied.com>

lib/src/models/rules/insert.dart

@@ -560,13 +560,15 @@ class PreserveInlineStylesRule extends InsertRule {
 
     final itr = DeltaIterator(document);
     var prev = itr.skip(len == 0 ? index : index + 1);
-    if (prev == null ||
-        (prev.data is String && (prev.data as String).endsWith('\n'))) {
-      prev = itr.next();
-    }
 
-    if (prev.data is! String) {
-      return null;
+    if (prev == null || prev.data is! String) return null;
+
+    if ((prev.data as String).endsWith('\n')) {
+      if (prev.attributes?.containsKey(Attribute.list.key) == true) {
+        return null;
+      }
+      prev = itr
+          .next(); // at the start of a line, apply the style for the current line and not the style for the preceding line
     }
 
     final attributes = prev.attributes;